No abstract

We present the key results from an intensive and coordinated ten-year amateur observational programme designed to uncover and confirm Galactic planetary nebulae (PNe). This was undertaken and led by a dedicated group of largely French amateur astronomers in collaboration with professional colleagues. Over this period this group has uncovered a total of 209 spectroscopically confirmed True, Likely, and Possible Galactic PNe, with the work accelerating over the last three years in particular. These new discoveries represent ~5% of all 3831 True, Likely, and Possible Galactic PNe currently known according to the HASH database as of March 2022. A further 610 PNe candidates are awaiting follow-up. These figures demonstrate the power and value of the amateur community in undertaking a coordinated and focused programme such as this.

Recently, the discovery and characterization of a new accreting-only symbiotic star THA 15–31 was presented. Motivated by the suggestion that the optical spectrum of the star might show the emission lines with higher ionization potential in comparison with previously studied epochs, we have obtained a low-resolution spectrum of this target. The spectrum does not reveal the presence of suggested He ii emission lines. Moreover, the near-UV excess seems to be even less prominent now in comparison with the previous observations, suggesting a decrease in mass transfer and accretion rate. The search for He ii emission lines should be repeated when the accretion rate is higher.